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1:22 AM
I thought the message was posted but not... internet is not working well. I return... So we have a trial function of the form $\Phi = \sum_{i=1}^{10} c_i \psi_i$, where every $\psi_i$ satisfiies the boundary condition of that problem. So the task is easy: 1. We solve the secular equation to find the 10 approximations $e_i$ for the 10 lowest bounded energy states of the Schrodinger's equation.
2. We go back to the system of linear equations to find the 10 coefficients that define $\Phi$ for the lowest state, then the 1st excited state, and so on. That would be 100 coefficients, in total.
Suppose we have made excellent guesses for the 10 first levels, even though the energy eigenvalues of the Hamiltonian are unknown to us. The question is the following: is there any guarantee that the expectation value of any quantum mechanical operator (angular momentum, electric dipole moment, kinetic energy, square displacement, etc.) are going to be better guesses of the real ones?
In other words, obtaining lower and lower energy eigenvalues with the variational method (or any other), does it imply necessarily better predictions for mean values?
 
 
10 hours later…
11:56 AM
What's the name of that oxygen compound that's described as smelling like rain after a thunderstorm? It seems like, not ozone, tri-something, was investigated as a hospital disinfectant at one point, it's on the tip of my tongue :-D
 
 
7 hours later…
7:05 PM
3
Q: Jablonski diagram and absorption

MäßigeI was reading about Jablonski diagrams and how they are structured. Bold lines would indicate ground electronic levels, and thin lines indicate the associated vibrational levels. Absorption only happens between the different electron energy (orbital) levels, however any additional associated vibr...

 
 
1 hour later…
8:21 PM
1
Q: Change of equilibrium constant with respect to temperature

PravimishSuppose we have an arbitrary chemical reaction $A+B\rightleftharpoons 2C+D$ and its equilibrium constant at two temperatures $T_{1},T_{2}$ are $k_{1},k_{2}$. We can relate them as $$\log\frac{k_{2}}{k_{1}}=\frac{\Delta H}{2.303R}\left(\frac{1}{T_{1}}-\frac{1}{T_{2}}\right)\ \ \ \ -(i)$$ I am unc...

 

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